Ballparks: Haymakers' Grounds & Riverside Park ·
Park Factors Over 100 favors batters, under 100 favors pitchers.
multi-year: Batting - 104, Pitching - 105 · one-year: Batting - 110, Pitching - 111
Transactions listed are from October 1 of previous year to April 1 of the following year.
Signed Roger Connor as a free agent.
Signed Mickey Welch as a free agent.
August, 1880 (Standings)
Signed Tim Keefe as a free agent.
September, 1880 (Standings)
Signed Buck Ewing as a free agent. (Date given is approximate. Exact date is uncertain.)